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Riau AK, Look Z, Yam GHF, Boote C, Ma Q, Han EJY, Binte M Yusoff NZ, Ong HS, Goh TW, Binte Halim NSH, Mehta JS. Impact of keratocyte differentiation on corneal opacity resolution and visual function recovery in male rats. Nat Commun 2024; 15:4959. [PMID: 38862465 PMCID: PMC11166667 DOI: 10.1038/s41467-024-49008-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 05/17/2024] [Indexed: 06/13/2024] Open
Abstract
Intrastromal cell therapy utilizing quiescent corneal stromal keratocytes (qCSKs) from human donor corneas emerges as a promising treatment for corneal opacities, aiming to overcome limitations of traditional surgeries by reducing procedural complexity and donor dependency. This investigation demonstrates the therapeutic efficacy of qCSKs in a male rat model of corneal stromal opacity, underscoring the significance of cell-delivery quality and keratocyte differentiation in mediating corneal opacity resolution and visual function recovery. Quiescent CSKs-treated rats display improvements in escape latency and efficiency compared to wounded, non-treated rats in a Morris water maze, demonstrating improved visual acuity, while stromal fibroblasts-treated rats do not. Advanced imaging, including multiphoton microscopy, small-angle X-ray scattering, and transmission electron microscopy, revealed that qCSK therapy replicates the native cornea's collagen fibril morphometry, matrix order, and ultrastructural architecture. These findings, supported by the expression of keratan sulfate proteoglycans, validate qCSKs as a potential therapeutic solution for corneal opacities.
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Affiliation(s)
- Andri K Riau
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore, 169856, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Programme, Duke-NUS Medical School, Singapore, 169857, Singapore
| | - Zhuojian Look
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore, 169856, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Programme, Duke-NUS Medical School, Singapore, 169857, Singapore
| | - Gary H F Yam
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore, 169856, Singapore
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Craig Boote
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, CF24 4HQ, UK
| | - Qian Ma
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, CF24 4HQ, UK
| | - Evelina J Y Han
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore, 169856, Singapore
| | - Nur Zahirah Binte M Yusoff
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore, 169856, Singapore
| | - Hon Shing Ong
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore, 169856, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Programme, Duke-NUS Medical School, Singapore, 169857, Singapore
- Corneal and External Eye Disease Department, Singapore National Eye Centre, Singapore, 168751, Singapore
| | - Tze-Wei Goh
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore, 169856, Singapore
| | | | - Jodhbir S Mehta
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore, 169856, Singapore.
- Ophthalmology and Visual Sciences Academic Clinical Programme, Duke-NUS Medical School, Singapore, 169857, Singapore.
- Corneal and External Eye Disease Department, Singapore National Eye Centre, Singapore, 168751, Singapore.
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2
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Miralles E, Kamma-Lorger CS, Domènech Ò, Sosa L, Casals I, Calpena AC, Silva-Abreu M. Assessment of Efficacy and Safety Using PPAR-γ Agonist-Loaded Nanocarriers for Inflammatory Eye Diseases. Int J Mol Sci 2022; 23:ijms231911184. [PMID: 36232486 PMCID: PMC9570464 DOI: 10.3390/ijms231911184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 09/18/2022] [Accepted: 09/19/2022] [Indexed: 11/16/2022] Open
Abstract
Drug-loaded nanocarriers (NCs) are new systems that can greatly improve the delivery and targeting of drugs to specific tissues and organs. In our work, a PPAR-γ agonist loaded into polymeric NCs was prepared, stabilized by spray-drying, and tested in vitro, ex vivo, and in vivo (animal models) to provide a safe formulation for optical anti-inflammatory treatments. The NCs were shown to be well tolerated, and no signs of irritancy or alterations of the eye properties were detected by the in vitro HET-CAM test and in vivo Draize test. Furthermore, no signs of cytotoxicity were found in the NC formulations on retinoblastoma cells (Y-79) analyzed using the alamarBlue assay, and the transmittance experiments evidenced good corneal transparency with the formulations tested. The ocular anti-inflammatory study confirmed the significant prevention efficacy using the NCs, and these systems did not affect the corneal tissue structure. Moreover, the animal corneal structure treated with the NCs was analyzed using X-ray diffraction using synchrotron light. Small-angle X-ray scattering (SAXS) analysis did not show a significant difference in corneal collagen interfibrillar spacing after the treatment with freshly prepared NCs or NCs after the drying process compared to the corresponding negative control when inflammation was induced. Considering these results, the PPAR-γ agonist NCs could be a safe and effective alternative for the treatment of inflammatory ocular processes.
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Affiliation(s)
- Esther Miralles
- CCiTUB (Scientific and Technological Centers), University of Barcelona, 08028 Barcelona, Spain
| | | | - Òscar Domènech
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Lilian Sosa
- Pharmaceutical Technology Research Group, Faculty of Chemical Sciences and Pharmacy, National Autonomous University of Honduras (UNAH), Tegucigalpa 11101, Honduras
| | - Isidre Casals
- CCiTUB (Scientific and Technological Centers), University of Barcelona, 08028 Barcelona, Spain
| | - Ana Cristina Calpena
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Marcelle Silva-Abreu
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
- Correspondence: ; Tel.: +34-93-402-4578
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3
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Zhao N, Yang C, Bian F, Guo D, Ouyang X. SGTools: a suite of tools for processing and analyzing large data sets from in situ X-ray scattering experiments. J Appl Crystallogr 2022. [DOI: 10.1107/s1600576721012267] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
In situ synchrotron small-angle X-ray scattering (SAXS) is a powerful tool for studying dynamic processes during material preparation and application. The processing and analysis of large data sets generated from in situ X-ray scattering experiments are often tedious and time consuming. However, data processing software for in situ experiments is relatively rare, especially for grazing-incidence small-angle X-ray scattering (GISAXS). This article presents an open-source software suite (SGTools) to perform data processing and analysis for SAXS and GISAXS experiments. The processing modules in this software include (i) raw data calibration and background correction; (ii) data reduction by multiple methods; (iii) animation generation and intensity mapping for in situ X-ray scattering experiments; and (iv) further data analysis for the sample with an order degree and interface correlation. This article provides the main features and framework of SGTools. The workflow of the software is also elucidated to allow users to develop new features. Three examples are demonstrated to illustrate the use of SGTools for dealing with SAXS and GISAXS data. Finally, the limitations and future features of the software are also discussed.
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Silva-Abreu M, Miralles E, Kamma-Lorger CS, Espina M, García ML, Calpena AC. Stabilization by Nano Spray Dryer of Pioglitazone Polymeric Nanosystems: Development, In Vivo, Ex Vivo and Synchrotron Analysis. Pharmaceutics 2021; 13:pharmaceutics13111751. [PMID: 34834165 PMCID: PMC8617923 DOI: 10.3390/pharmaceutics13111751] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 10/10/2021] [Accepted: 10/13/2021] [Indexed: 12/13/2022] Open
Abstract
Pioglitazone-loaded PLGA-PEG nanoparticles (NPs) were stabilized by the spray drying technique as an alternative to the treatment of ocular inflammatory disorders. Pioglitazone-NPs were developed and characterized physiochemically. Interaction studies, biopharmaceutical behavior, ex vivo corneal and scleral permeation, and in vivo bioavailability evaluations were conducted. Fibrillar diameter and interfibrillar corneal spacing of collagen was analyzed by synchrotron X-ray scattering techniques and stability studies at 4 °C and was carried out before and after the spray drying process. NPs showed physicochemical characteristics suitable for ocular administration. The release was sustained up to 46 h after drying; ex vivo corneal and scleral permeation profiles of pioglitazone-NPs before and after drying demonstrated higher retention and permeation through cornea than sclera. These results were correlated with an in vivo bioavailability study. Small-angle X-ray scattering (SAXS) analysis did not show a significant difference in the organization of the corneal collagen after the treatment with pioglitazone-NPs before and after the drying process, regarding the negative control. The stabilization process by Nano Spray Dryer B-90 was shown to be useful in preserving the activity of pioglitazone inside the NPs, maintaining their physicochemical characteristics, in vivo bioavailability, and non-damage to corneal collagen function after SAXS analysis was observed.
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Affiliation(s)
- Marcelle Silva-Abreu
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; (M.E.); (M.L.G.); (A.C.C.)
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
- Correspondence: ; Tel.: +34-93-402-4578
| | - Esther Miralles
- CCiTUB (Scientific and Technological Centers), University of Barcelona, 08028 Barcelona, Spain;
| | | | - Marta Espina
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; (M.E.); (M.L.G.); (A.C.C.)
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - María Luisa García
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; (M.E.); (M.L.G.); (A.C.C.)
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Ana Cristina Calpena
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; (M.E.); (M.L.G.); (A.C.C.)
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
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Hayes S, Aldahlawi N, Marcovich AL, Brekelmans J, Goz A, Scherz A, Young RD, Bell JS, O'Brart DP, Nuijts RMMA, Meek KM. The effect of bacteriochlorophyll derivative WST-D and near infrared light on the molecular and fibrillar architecture of the corneal stroma. Sci Rep 2020; 10:9836. [PMID: 32555309 PMCID: PMC7299946 DOI: 10.1038/s41598-020-66869-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 05/28/2020] [Indexed: 11/30/2022] Open
Abstract
A cross-linking technique involving application of Bacteriochlorophyll Derivative WST-11 mixed with dextran (WST-D) to the epithelium-debrided cornea and illumination with Near Infrared (NIR), has been identified as a promising therapy for stiffening pathologically weakened corneas. To investigate its effect on corneal collagen architecture, x-ray scattering and electron microscopy data were collected from paired WST-D/NIR treated and untreated rabbit corneas. The treated eye received 2.5 mg/mL WST-D and was illuminated by a NIR diode laser (755 nm, 10 mW/cm2). An increase in corneal thickness (caused by corneal oedema) occurred at 1-day post-treatment but resolved in the majority of cases within 4 days. The epithelium was fully healed after 6–8 days. X-ray scattering revealed no difference in average collagen interfibrillar spacing, fibril diameter, D-periodicity or intermolecular spacing between treated and untreated specimens. Similarly, electron microscopy images of the anterior and posterior stroma in healed WST-D/NIR corneas and untreated controls revealed no obvious differences in collagen organisation or fibril diameter. As the size and organisation of stromal collagen is closely associated with the optical properties of the cornea, the absence of any large-scale changes following treatment confirms the potential of WST-D/NIR therapy as a means of safely stiffening the cornea.
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Affiliation(s)
- S Hayes
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom.
| | - N Aldahlawi
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom
| | - A L Marcovich
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel.,Department of Ophthalmology, Kaplan Medical Center, Rehovot, Israel
| | - J Brekelmans
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel.,University Eye Clinic Maastricht, Maastricht University Medical Center, Maastricht, the Netherlands
| | - A Goz
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel.,Department of Ophthalmology, Kaplan Medical Center, Rehovot, Israel
| | - A Scherz
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - R D Young
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom
| | - J S Bell
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom
| | - D P O'Brart
- Keratoconus Research Institute, Department of Ophthalmology, St Thomas Hospital, London, United Kingdom
| | - R M M A Nuijts
- University Eye Clinic Maastricht, Maastricht University Medical Center, Maastricht, the Netherlands
| | - K M Meek
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom
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Feneck EM, Souza RB, Lewis PN, Hayes S, Pereira LV, Meek KM. Developmental abnormalities in the cornea of a mouse model for Marfan syndrome. Exp Eye Res 2020; 194:108001. [PMID: 32173378 PMCID: PMC7232021 DOI: 10.1016/j.exer.2020.108001] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 02/14/2020] [Accepted: 03/09/2020] [Indexed: 11/17/2022]
Abstract
Elastic fibres provide tissues with elasticity and flexibility. In the healthy human cornea, elastic fibres are limited to the posterior region of the peripheral stroma, but their specific functional role remains elusive. Here, we examine the physical and structural characteristics of the cornea during development in the mgΔloxPneo dominant-negative mouse model for Marfan syndrome, in which the physiological extracellular matrix of its elastic-fibre rich tissues is disrupted by the presence of a dysfunctional fibrillin-1 glycoprotein. Optical coherence tomography demonstrated a reduced corneal thickness in the mutant compared to wild type mice from embryonic day 16.5 until adulthood. X-ray scattering and electron microscopy revealed a disruption to both the elastic fibre and collagen fibril ultrastructure in the knockout mice, as well as abnormally low levels of the proteoglycan decorin. It is suggested that these alterations might be a result of increased transforming growth factor beta signalling. To conclude, this study has demonstrated corneal structure and ultrastructure to be altered when fibrillin-1 is disrupted and has provided insights into the role of fibrillin-1 in developing a functional cornea. mgΔloxPneo mice showed abnormalities in corneal thickness from embryonic development through to adulthood. Elastic fibres were evident from E16.5 in both the WT and mgΔloxPneo mouse corneas. Adult mgΔloxPneo mouse corneas exhibited a disorganised elastic fibre network with unusually high levels of branching. The disrupted collagen arrangement seen in adult mgΔloxPneo mice corneas is likely linked to lower levels of decorin in these corneas.
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Affiliation(s)
- Eleanor M Feneck
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK
| | - Rodrigo B Souza
- Department of Genetics and Evolutionary Biology, University of Sᾶo Paulo, Rua do Matᾶo, Sᾶo Paulo, Brazil
| | - Philip N Lewis
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK
| | - Sally Hayes
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK
| | - Lygia V Pereira
- Department of Genetics and Evolutionary Biology, University of Sᾶo Paulo, Rua do Matᾶo, Sᾶo Paulo, Brazil
| | - Keith M Meek
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK.
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Abstract
X-ray scattering enables the structure of collagen-rich tissues, such as the cornea, to be examined at both the molecular and fibrillar level. The high-intensity X-rays available at synchrotron radiation sources, coupled with minimal sample preparation requirements, facilitates the rapid generation of high-quality X-ray scattering data from corneal tissue at a close-to-physiological state of hydration. Analysis of resulting X-ray scatter patterns allows one to quantify numerous structural parameters relating to the average diameter, lateral arrangement and alignment of collagen fibrils within the cornea, as well as the axial and lateral arrangements of collagen molecules within the fibrils. Here we describe the typical experimental setup and considerations involved in the collection of X-ray scattering data from corneal tissue.
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Affiliation(s)
- Keith M Meek
- Structural Biophysics Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK.
| | - Andrew J Quantock
- Structural Biophysics Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| | - Sally Hayes
- Structural Biophysics Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| | - James Bell
- Structural Biophysics Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
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Revealing the assembly of filamentous proteins with scanning transmission electron microscopy. PLoS One 2019; 14:e0226277. [PMID: 31860683 PMCID: PMC6924676 DOI: 10.1371/journal.pone.0226277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/22/2019] [Indexed: 11/19/2022] Open
Abstract
Filamentous proteins are responsible for the superior mechanical strength of our cells and tissues. The remarkable mechanical properties of protein filaments are tied to their complex molecular packing structure. However, since these filaments have widths of several to tens of nanometers, it has remained challenging to quantitatively probe their molecular mass density and three-dimensional packing order. Scanning transmission electron microscopy (STEM) is a powerful tool to perform simultaneous mass and morphology measurements on filamentous proteins at high resolution, but its applicability has been greatly limited by the lack of automated image processing methods. Here, we demonstrate a semi-automated tracking algorithm that is capable of analyzing the molecular packing density of intra- and extracellular protein filaments over a broad mass range from STEM images. We prove the wide applicability of the technique by analyzing the mass densities of two cytoskeletal proteins (actin and microtubules) and of the main protein in the extracellular matrix, collagen. The high-throughput and spatial resolution of our approach allow us to quantify the internal packing of these filaments and their polymorphism by correlating mass and morphology information. Moreover, we are able to identify periodic mass variations in collagen fibrils that reveal details of their axially ordered longitudinal self-assembly. STEM-based mass mapping coupled with our tracking algorithm is therefore a powerful technique in the characterization of a wide range of biological and synthetic filaments.
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The hierarchical response of human corneal collagen to load. Acta Biomater 2018; 65:216-225. [PMID: 29128531 PMCID: PMC5729024 DOI: 10.1016/j.actbio.2017.11.015] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 11/05/2017] [Accepted: 11/07/2017] [Indexed: 02/04/2023]
Abstract
Fibrillar collagen in the human cornea is integral to its function as a transparent lens of precise curvature, and its arrangement is now well-characterised in the literature. While there has been considerable effort to incorporate fibrillar architecture into mechanical models of the cornea, the mechanical response of corneal collagen to small applied loads is not well understood. In this study the fibrillar and molecular response to tensile load was quantified using small and wide angle X-ray scattering (SAXS/WAXS), and digital image correlation (DIC) photography was used to calculate the local strain field that gave rise to the hierarchical changes. A molecular scattering model was used to calculate the tropocollagen tilt relative to the fibril axis and changes associated with applied strain. Changes were measured in the D-period, molecular tilt and the orientation and spacing of the fibrillar and molecular networks. These measurements were summarised into hierarchical deformation mechanisms, which were found to contribute at varying strains. The change in molecular tilt is indicative of a sub-fibrillar “spring-like” deformation mechanism, which was found to account for most of the applied strain under physiological and near-physiological loads. This deformation mechanism may play an important functional role in tissues rich in fibrils of high helical tilt, such as skin and cartilage. Statement of Significance Collagen is the primary mediator of soft tissue biomechanics, and variations in its hierarchical structure convey the varying amounts of structural support necessary for organs to function normally. Here we have examined the structural response of corneal collagen to tensile load using X-rays to probe hierarchies ranging from molecular to fibrillar. We found a previously unreported deformation mechanism whereby molecules, which are helically arranged relative to the axis of their fibril, change in tilt akin to the manner in which a spring stretches. This “spring-like” mechanism accounts for a significant portion of the applied deformation at low strains (<3%). These findings will inform the future design of collagen-based artificial corneas being developed to address world-wide shortages of corneal donor tissue.
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